Darling Mine
by SilveryMoon34
Summary: Following a bad break up and a resulting accident, Red goes to stay with his cousin Sans a state away. New town, new school, a fresh start, what could possibly go wrong? (Sister fic to Enemy Mine, based on nasty-bones's Underclass AU. Mostly likely will contain porn in later chapters) UT!Sans/US!Papyrus, UF!Sans/UF!Papyrus
1. Chapter 1

**A/N: Based on nasty-bones's lovely AU Underclass. Technically a sister fic to my previous, Enemy Mine, but you don't have to read it to get what's going on. In my headcanon for this AU, Underfell Sans (Red) and classic Sans are cousins. The Papses and Sanses are not related to each other, just classmates, but I'm tagging Fontcest anyway just in case.**

 **PS: if anyone's interested, Red's listening to My House by Pvris in the car.**

 **Darling Mine**

So. Visiting the cousin, nearly a state away. Red would be lying if he said he wasn't even a little nervous-he hadn't seen the little squirt since they were small, barely into elementary school.

But...Honestly? With everything that's happened to him recently, he was more than happy to get away. And it wasn't like he hated the idea-they'd gotten along well enough as kids, both equally obsessed with science, as their fathers were. And, bonus, the kid lived alone, so it wasn't like there would be an adult to breathe down their necks. His neck. And right now, that sounded like heaven.

In the passenger seat, his phone went off. He didn't have to look at it to know who it was. He ignored it, rolling down the windows and turning up the radio.

This was more than just an escape. This was him turning over a new leaf. Starting fresh. Cutting off old relationships for good, putting his big brainpower back into school and being a better monster. No more fuck ups for him, accidental or otherwise.

This was gonna be his best semester yet, he was sure of it.

Sans's house was a cute, modest two-story in an older, quieter neighborhood. Despite driving like a bat out of hell, racing the sun itself, Red arrived well into the evening; a small light glowed in what he guessed was the living room. He shut off the car, inhaling deeply before pushing open the door.

Any nervousness about his reception was immediately blasted away. A blue blur launched off the porch, yanking him into a hug.

"Hi Red!" Sans squeezed around his middle. A laugh bubbled out from somewhere deep inside as Red hugged back, lifting his smaller cousin up easily.

"Hey, squirt. Glad to see you're still so tiny. Like a lil doll!"

Sans playfully smacked his shoulder, wiggling until he was put back down. "You're not much taller, jerk. Come on. I'll show you your room."

"'Kay." Red grabbed his duffle, trotting after.

"Oh! Bags!" Sans turned on the spot, blinking in surprise at Red's one bag. "Um. That's not the only one, right?"

"Pssht, 'course not. The other one can wait, though. I'm bushed. And I'm sure it's past your bedtime."

Sans made a face-it was way too cute and nonthreatening to be called a glare. "We're the same age, Red. I don't have or need a bedtime."

"Sure you don't, squirt."

The guest room was really nice, with a big bed and its own bathroom. Sans was spoiling him-he'd have been happy with a couch and a closet to dump his crap in.

"Hey-" he began, turning. Sans's eyes widened-Red had caught him in the middle of suppressing a yawn. He snorted. "Go to bed, squirt. We're family, ya don't have to be a good host."

Sans smiled sheepishly, but didn't protest. "Night, Red."

"Night. And...hey." Sans stopped at the doorway, turning back curiously. "Thanks, Sans."

Sans smiled back softly. "No problem. Like you said, we're family."

"Right. G'night."

Sans waved, continuing on, back to his room. Red listened to his footsteps pad away, smile dropping. He blew out a breath, rubbing his face. Alone, with no road to distract, earlier's bravado slipped. He felt his phone in his jacket pocket, it's slim form seemingly as heavy as a brick.

...He wouldn't call him. Fuck no. But the asshole would've left more messages, and if he didn't delete 'em, they'd pile up and fill his inbox. Yeah.

He sank down on the bed, pulling it out.

Yep. 10 missed calls, two voicemail messages. His thumb hovered over the delete button…

...He pressed play.

The first, left this morning, was brief and to the point: "Red! Answer your fucking phone, for fuck's sake!"

Hearing Boss's voice, unchanged despite everything, felt like a hug followed by a punch to the gut. Red deleted it.

The second, left not too long ago, was less so: "Thanks a lot, asshole. Thanks for letting me know you were still fucking alive. I had to find out from that nosy bitch Dogaressa. Fucking _Dogaressa!_ By the time she told me, the entire fucking school knew-"

"Ohwhy the fuck do _you_ care, anyway?" Red growled, even though he knew his boyf- _former_ boyfriend couldn't hear. There was more, but Red deleted it, too pissed off to care.

He tossed the phone onto the nightstand, flopping back on the soft blankets. He wasn't going to cry. He wasn't. Going. To fucking cry. Getting upset is what got him here in the first place.

He kicked off his shoes, ripping off his jacket. He never bothered with pajamas; an undershirt and boxers worked just fine. He dropped his shirt and pants on the floor, getting under the blankets and throwing an arm over his eye sockets.

It didn't work. He still felt the treacherous prickle underneath his arm. He groaned, pulling himself out of bed.

Only one thing would keep crybaby tears at bay, and that was getting plastered. Before he'd left, he 'helped himself' to a bottle of his dad's best monster moonshine. Served the old ass right for sending him away. He'd meant to share it with Sans, as a thank you for letting him crash here on such short notice, but fuck it. Little goody goody squirt probably didn't even drink anyway.

He didn't bother with fetching a glass, just took the whole bottle back to bed with him. He closed his eye sockets, taking the biggest pull off of it he could manage. He shivered at the burn, welcoming the slight pain. Normal human liquor could get even a skeleton monster drunk, but it took a lot of it-enough to kill a human-and the buzz never lasted long. Magic burned it out of the system fairly quickly, just like human food. If he drank this whole bottle of magic-based liquor, though, the buzz might last him till lunch tomorrow, if he didn't pass out or sleep it off first.

It was a game he played often, and knew all too well.


	2. Chapter 2

**A/N: And here's chapter 2. Sorry in advance for the short chapters so far. Easier to find motivation to type them up that way. They'll get longer as crap starts to hit the fan, though.**

 **Chapter 2**

"Red! Get up! We've got to get ready for school!"

Joke's on him-he'd watched the sky steadily grow lighter through the guest room's wall of windows for the past hour or so, stuck in that breezy, buzzed state between awake and asleep.

He dropped the empty bottle, finding satisfaction in its dull thump against the thick carpet. He hopped up-whoops, too far, was there always a wall there? Oh right. Not his house. Not his room.

He pushed away from it, stretching as tall as his small frame could manage, back and joints popping deliciously. He decided, not for the first time, that he liked this swishy feeling, like bubbles in his nonexistent stomach.

"Red!"

 _Ohright. Focus. Uniform_. He made a face, padding towards the closet, where he'd dumped his duffle. What kind of dorky-ass school needed a uniform, anyway? Were they afraid all the students would wander off without them, like ducklings?

He grinned at the image. "Quack."

He couldn't hold it in at that, it was just too ridiculous. He sat down hard on his rear in front of the closet, giggling like it was the funniest thing he ever heard in his life. He still managed to pull his duffle the rest of the way to him, somehow.

It took a couple of tries to find what he was looking for, and even more to get each piece on the right body part in the right order. Satisfied at that he was the epitome of a proper schoolboy in his proper monkey suit, he snagged his keys off the nightstand, marching out to meet his cousin.

Sans, already immaculate of course, took one look at him and sighed, a sharp blast out his nose. Kinda like an elephant, 'cept Sans was _sans_ a trunk. He couldn't help it. The giggle fit started all over again, though he miraculously managed to stay on his feet this time.

"...You're drunk, aren't you?"

"Eeeeeyup." He got why humans liked to say that now. It just sorta rolled off the tongue, in a nice way that felt good against his teeth.

Sans clicked his at him, conjured blue flashing behind the white as he fussed, smoothing a few creases out of Red's (untucked) shirt, straightening his jacket. Even tying his tie, despite Red's groan of protest.

"Are ya done now, mom?" he grumbled. He definitely wasn't pouting, though. He wasn't a babybones.

"Close enough. Come on. We gotta hurry or we'll be late for the bus."

"Pfft, screw the bus." He held up his keys, jingling them in Sans's face. "Got a _car_ , squirt."

Sans looked at him as if he'd just swore in front of the principal. "I can't drive, and you're _drunk!_ "

"Can't drive?" Red pulled his hand back, tossing his keys to Sans with surprising accuracy. "Put on your big boy pants, kid. You gon' learn."

"I c-can't! Are you crazy?!"

"Noooo, I'm drunk." He winked, weaving his way towards the front door. Sans checked his watch, groaned, and followed after, gripping the keys in a way that had to hurt.

Despite Sans's high pitched running commentary ("Oh stars Red we're gonna die your first day here and I'm gonna accidentally kill you in a horrible _car crash_ I'm sorry I'm sososorry!") that went on, completely oblivious to Red's expert assurances ("Eyes on the road, squirt! Face our potential deaths like a monster, not a babybones!") they arrived safely at school, with plenty of time to spare.

Sans more or less jumped from the car the second it was parked, breathing as if he'd run the entire way. He pressed a small hand over his chest, almost wheezing. Grinning, Red slung an arm around his shoulders, soul warm with affectionate pride.

"Attaboy. Knew you could do it."

Sans shoved the keys back into his hand. "Never again! Stars, I hate you so much right now."

"Love ya too, squirt."

Catching his breath at last, Sans turned back to the car, as if looking for something. Red was one step ahead; he held Sans's bag out to him, still grinning. The smaller snatched it back, primly adjusting his glasses.

"Come on, jerk. You don't want to be late on your first day."

"Whyyyyy? 'Fraid I'll make ya look bad?"

Sans slanted a look at him, completely unimpressed. "No. It's just bad form."

Red wanted to laugh it off, but he'd come down off his buzz enough to admit, at least to himself, that Sans was right. It was such a little thing, but if he really wanted all this to be a proper do over, getting off (ha) on the right foot with his teachers was the first step. Showing up late wouldn't exactly earn him their good graces, not in a strict and proper school like this. So, for once in his life he shut his smart mouth, easily falling into step beside his cousin.

They'd barely gotten inside, when some tall asshole had the gall to steal his cousin's glasses right off his face from behind, quick as you please.

So. It was that kind of school, was it? Quick as they were, Red was quicker; he turned smartly on his heel, fist smashing into the dickbag's ribcage before they could even think about running off, knocking 'em on their ass with a satisfying thud. Red caught Sans's glasses with his magic like a proper fucking hero, his still semi-drunk mind already supplying the deserved level of appreciation and awe.

As usual, reality was much different. Sans snatched his glasses back, glaring at him like _he_ was the bad guy. "Red! That's my _boyfriend_."

His...whuh? Said boyfriend groaned from the floor, holding his ribs. Whoops. "Oops. Sorry. Good thing I didn't go for the face then, eh big guy?" Thankfully, the guy cracked a small smile at that, readily accepting Red's offered hand. He pulled him up-jeez, he was big. Opposites attract, he guessed.

"Okay there, Stretch?"

"Papyrus," Sans corrected shortly, right eye sparking blue for a brief second. Whoops indeed. "His name is Papyrus."

"Heh, yeah. What he said," Papyrus confirmed, shaking the hand still in his grip. "So you're the cousin. I think I like you already."

Red snorted. Funny jolly orange giant, wasn't he? "D'ya normally say that to a guy who just knocked you on your ass?"

"Eh? Not normally, no." Papyrus grinned, bright and infectious. "It's never happened before."

Wow, Stretch. How d'you get through doorways with that ego? "Savor the feelin', Stretch. In the interest of _not_ being murdered in my sleep by the squirt, it won't be happenin' again."

"Fair enough," he allowed with a wink. Sans groaned, grabbing his boyfriend's arm, pulling him along.

"Come on, you two. Classes will be starting any minute."

Pap rolled his eye lights, heaved a fake sigh, but went along with his small boyfriend tamely enough. He took his arm back, only to wrap it around Sans's shoulders, pulling him close. Sans, in turn, leaned into him, sliding an arm around his narrow waist. The movements were completely natural, neither breaking stride-like they did this every day. Hell, they probably did.

Red felt his soul pulse painfully, sharp but not unexpected. They were exactly the sort of sickly sweet couple he and...and Boss would've made fun of together. The sort of couple Red secretly envied.

 _But it hadn't been all bad, had it?_ A quiet, deceptively reasonable-sounding voice in his head said. No, it hadn't. In fact those two years had been the best of his life. But then Boss had to go throw them, all of them, the good and the bad, away like trash when he...Red shoved those thoughts, those memories, away. Good or bad, they didn't matter anymore. Right here mattered. Right _now_ mattered. He had his whole life ahead of him. Damned if he was gonna waste any of it mourning something that obviously never meant as much as he thought it did.

He pushed forward, wishing he had just pled sickness and stayed in bed that morning.

 **A/N: Tfw your boyfriend tries to be cute and your overprotective cousin punches the shit out of him. Also, poor Red. Don't worry, though, there will be a happy ending to all this angst. Eventually. More to come.**


End file.
